A web-based group decision support system for multicriteria ranking problems

In this paper, we present an implemented, web‐based multicriteria group decision support system for solving multicriteria ranking problems by a collaborative group of decision‐makers in sequential or parallel coordination mode and in a distributed and asynchronous environment. This system employs an order‐based consensus model for collaborative groups that moves from consistency to consensus. The system is based on consensus measures and it has been designed to provide advice to the decision‐makers to increase group consensus level while maintaining the individual consistency of each decision‐maker. It is based on the use of fuzzy outranking relations to model individual and group preferences. For the exploitation of the models–formulated as a multiobjective optimization problem and solved with a multiobjective evolutionary algorithm–the system generates advice on how decision‐makers should change their preferences to reach a ranking of alternatives with a high degree of consistency and consensus.